Vaccine最新文献

Vaccine development targeting Mycoplasma pneumoniae began in the 1960s, but achieving safe and effective immunization is still challenging. Careful consideration of the immunization pathway is one of the critical aspects of vaccine development. In this investigation, C57BL/6 J mice were intragastrically vaccinated with live M. pneumoniae, and the short-term safety and resultant immune effects were evaluated. Oral administration likely demonstrated intestinal clearance with restricted systemic dissemination and no tissue pathogenicity in both the intestinal and pulmonary tracts. Furthermore, the oral vaccination with live M. pneumoniae effectively reduced the pathogen burden in the lung, alleviated pulmonary inflammation, and reduced the pulmonary secretion of IL-1β and TNF-α after intranasal bacterial infection 3 or 15 weeks after the last dose. Moreover, Airway exposure to M. pneumoniae in live pathogen intragastric vaccinated mice triggered robust recall responses, marked by the elevation of systemic mycoplasma-specific IgG and IgM, alongside pulmonary mucosal IgA, paralleled by clonal expansion of Th1, Th2, and CTL. In conclusion, oral delivery presents a promising route for developing M. pneumoniae vaccines.

HPV-related oropharyngeal squamous cell carcinoma (OPSCC) has increased significantly among men, especially among men living with HIV. HPV vaccines have proven efficacy in preventing persistent anogenital HPV infections. However, less is known regarding vaccine efficacy against persistent oral HPV infection, the obligate precursor of OPSCC. In 2020, the 9-valent HPV (9vHPV) vaccine received accelerated approval from the FDA for the indication of prevention of HPV-related OPSCC and other head and neck cancers, pending confirmation of clinical benefit in further trials. Currently a Phase III trial is ongoing to evaluate efficacy of the 9vHPV vaccine in preventing persistent oral HPV infection in immunocompetent men (NCT04199689); however, no trials have been conducted in people living with HIV. Here we describe the rationale, design, and study population characteristics of the first randomized (1:1), double-blind, placebo-controlled trial evaluating the efficacy and immunogenicity of the 9vHPV vaccine in preventing persistent oral HPV infection in men aged 20-50 living with HIV. The primary objective is to demonstrate that the 9vHPV vaccine when given in a 3-dose regimen (Day 1, Months 2 and 6) reduces the incidence of persistent (≥6 months) oral HPV infection with 9vHPV vaccine types 6, 11, 16, 18, 31, 33, 45, 52, and 58 in men living with HIV who are oral HPV negative to the relevant HPV type at enrollment, compared with placebo. The trial began in February 2021 and completed enrollment of 700 men at clinical sites in Brazil, Mexico, and Puerto Rico in February 2024. The secondary objectives are to evaluate the vaccine-induced serum anti-HPV 6, 11, 16, 18, 31, 33, 45, 52, and 58 responses, and the safety and tolerability of the 9vHPV vaccine in men living with HIV. Results from this study may inform policy regarding vaccination strategies for people living with HIV. ClinicalTrials.gov Identifier: NCT04255849.

In recent years, the rabbit hemorrhagic disease virus 2(RHDV GI.2) has rapidly spread worldwide due to its broad natural host range, strong pathogenicity, and significant antigenic differences from the traditional RHDV1 (GI.1). The widespread prevalence of both GI.1 and GI.2 RHDV poses a serious threat to the healthy development of the global rabbit industry. Despite this, there is still a notable absence of effective multivalent or broad-spectrum vaccines for controlling RHD(GI.1 and GI.2). In the present study, we developed a broad-spectrum chimeric antigen vaccine using a substitution strategy targeting the surface loop of the main antigen protein VP60 of RHDV. The chimeric VP60 antigen, expressed by a recombinant baculovirus expression system, was successfully assembled into virus-like particles (VLPs). The VLPs exhibited typical natural virus size and morphology under an electron microscope. Immunization with chimeric VLPs effectively protected rabbits from lethal challenged by both virulent strains of RHDV, GI.1 and GI.2, showing an effect comparable to that of a mixture vaccine containing two wild-type VLPs. These findings demonstrate a promising strategy for developing a cost-effective and straightforward preparation process for broad-spectrum vaccine against RHD.

To determine the impact of pneumococcal vaccination on nasopharyngeal carriage in Tanzania, we assessed the serotype distribution of S. pneumoniae isolated from nasopharyngeal swab samples. These samples were collected in 539 children below the age of 5 years in two cross-sectional studies, one before and one after PCV13 rollout. In the second study, post-PCV13 rollout, only children who completed the PCV13 vaccination schedule, were included. From the study conducted before the introduction of PCV13, 61 (55 %) of S. pneumoniae serotypes were vaccine types, compared to 89 (23.3 %) post-PCV13. The most common serotypes in the pre-PCV13 period were 19F (n = 23, 20.7 %) and 6B (n = 11, 9.9 %). In the post-PCV13 era, serotypes 15B/C (n = 40, 10.5 %), and 3 (n = 29, 7.6 %) were most prevalent. We observed the emergence of 14 non-vaccine serotypes not detected in the pre-vaccine era. Further surveillance is needed to assess shifts in carriage and their implications for the protection against invasive pneumococcal disease.

The present study aimed to investigate the optimal inactivants and inactivation conditions for preparing inactivated vaccines of Mycoplasma hyopneumoniae and Mycoplasma hyorhinis. Mycoplasma inactivation was performed using formaldehyde, thimerosal, β-propiolactone (BPL), and binary ethylenimine (BEI) and compared. The results showed that M. hyopneumoniae was completely inactivated when incubated with 0.01 % formaldehyde for 24 h or 0.02 % formaldehyde for 12 h at 37 °C, with 0.0008 % thimerosal for 12 h at 37 °C, with 0.02 % BPL for 24 h or 0.1 % BPL for 12 h at 4 °C, or with 0.004 % BEI for 24 h or 0.5 % BEI for 12 h at 37 °C. M. hyorhinis was completely inactivated when incubated with 0.01 % formaldehyde for 24 h or 0.02 % formaldehyde for 12 h at 37 °C, with 0.004 % thimerosal for 24 h or 0.02 % thimerosal for 12 h at 37 °C, with 0.1 % BPL for 12 h at 4 °C, or with 0.004 % BEI for 24 h or 0.5 % BEI for 12 h at 37 °C. Next, the immunogenicity of the mycoplasmas after inactivation was evaluated by immunizing BALB/c mice. Immunization of mice with a high dose (10⁶ color-changing units [CCU] per dose) of M. hyopneumoniae and M. hyorhinis vaccines inactivated with all inactivants led to high levels of serum IgG antibodies. M. hyopneumoniae vaccines inactivated with formaldehyde induced significantly higher titers of antibodies than vaccines inactivated with other inactivants, whereas M. hyorhinis vaccines inactivated with BEI induced significantly higher titers of antibodies than vaccines inactivated with thimerosal. However, in mice immunized with a low dose of mycoplasmas (10⁴ CCU per dose), only M. hyopneumoniae vaccines inactivated with formaldehyde and BEI and M. hyorhinis vaccines inactivated with formaldehyde, BPL, and BEI led to significant levels of serum IgG antibodies. Among these groups, the antibody levels in the formaldehyde-inactivated vaccine group were higher than those in the other inactivant groups. This study provides a reliable basis for inactivation during large-scale production of Mycoplasma hyopneumoniae and Mycoplasma hyorhinis inactivated vaccines.

Purpose: Adolescents and young adults have lower uptake of vaccines for preventable diseases than children and older adults. Young adults with type 1 diabetes (T1D) are at risk of complications from many vaccine-preventable illnesses. Given the elevated health risks of SARS-COV-2 infection for people with T1D, it is important to understand COVID-19 vaccination rates and attitudes. We explored vaccine uptake and characterized self-reported reasons for declining vaccination in a cohort of young adults with T1D as they were leaving pediatric care during the COVID-19 pandemic.

Methods: Participants enrolled in a randomized controlled trial of a transition intervention for young adults with T1D reported COVID-19 vaccination at baseline (2/2021-6/2023). We report rates of COVID-19 vaccination in addition to demographic and medical characteristics. Participants who did not receive vaccination were asked to note the reason(s). From these qualitative responses we identified themes.

Results: Of the n = 97 participants reporting vaccination status, 70.1 % reported receiving at least one COVID-19 vaccine. No demographic or medical characteristics were significantly associated with vaccination status (p ≥ 0.05). Themes of reasons for not receiving the COVID-19 vaccination included Doubt, Fear, External Factors, and Indifference.

Discussion: In young adults with T1D, COVID-19 vaccine uptake is below public health targets. Addressing fears about vaccine-related effects on T1D, doubts surrounding vaccine development and efficacy, and other external factors influencing vaccination decisions may be helpful in initiating a dialogue between clinicians and young adults considering vaccination. Further investigation into attitudes about other preventative care measures in this vulnerable population is needed. Clinical trial registry site and number: ClinicalTrials.gov ID Number - NCT04247620.